This disclosure relates to polycarbonate compositions, and in particular to endcapped polycarbonate compositions, methods of manufacture, and uses thereof.
Polycarbonate is a high-performance plastic with good impact strength (ductility). However, polycarbonate often has relatively limited flow properties, which is needed in the manufacture of thin walled articles. Medium to high flow polycarbonate grades suffer from the fact that the low temperature ductility is sacrificed for a better flow. Furthermore, polycarbonate compositions often require the use of flame retardants to find successful use in the manufacture of a variety of articles and components.
A widely used method to increase low temperature impact resistance is the addition of impact modifiers, for example, methacrylate-butadiene-styrene (MBS) rubbers or acrylonitrile-butadiene-styrene (ABS) rubbers, to the polycarbonate compositions. In addition, flame retardants are often added to improve the flame retardant properties of the polycarbonate compositions. The drawback of these modifications is that, even with low addition levels, for example 1 weight percent, the transparency decreases, detracting one of the key properties of polycarbonate.
There accordingly remains a need in the art for high flow polycarbonate compositions and articles made from them that are transparent and flame retardant.